Support HTTPS and custom certificate

Secure client to server connection by using HTTPS and by
trusting our servers certificate only.

Signed-off-by: Martin Abente Lahaye <tch@sugarlabs.org>
Update default settings

Set all intervals to production values so it will (a) check
for active application each 15 seconds, (b) persist usage times
each 5 minutes, (c) allow to re-try failed reports after 30
minutes and (d) report to server once each 6 days.

Set URL to my local development server until we setup a production
server.

Signed-off-by: Martin Abente Lahaye <tch@sugarlabs.org>
Release 1.17

Signed-off-by: Martin Abente Lahaye <tch@sugarlabs.org>